<template>
  <div class="upload-file">
    <el-upload
      ref="upload"
      :action="uploadFileUrl"
      :before-upload="handleBeforeUpload"
      :file-list="fileList"
      :limit="limit"
      :on-error="handleUploadError"
      :on-exceed="handleExceed"
      :on-success="handleUploadSuccess"
      :show-file-list="false"
      :headers="headers"
      class="upload-file-uploader"
      :on-progress="handleUploadProgress"
      :disabled="limit === 1 && isUpLoading">
      <!-- 上传按钮 -->
      <el-button
        size="mini"
        type="primary"
        :icon="limit === 1 && isUpLoading ? 'el-icon-loading' : ''"
        :disabled="limit === 1 && isUpLoading">
        {{ limit === 1 && isUpLoading ? "上传中..." : "选取文件" }}
      </el-button>
      <!-- 上传提示 -->
      <div class="el-upload__tip" slot="tip" v-if="showTip">
        请上传
        <template v-if="fileSize"> 大小不超过 <b style="color: #f56c6c">{{ fileSize }}MB</b> </template>
        <template v-if="fileType"> 格式为 <b style="color: #f56c6c">{{ fileType.join("/") }}</b> </template>
        的文件
      </div>
    </el-upload>

    <!-- 文件列表 -->
    <transition-group class="upload-file-list el-upload-list el-upload-list--text" name="el-fade-in-linear" tag="ul">
      <li :key="file.url" class="el-upload-list__item ele-upload-list__item-content" v-for="(file, index) in fileList">
        <el-link :href="`${file.url}`" :underline="false" target="_blank">
          <span class="el-icon-document"> {{ getFileName(file.name) }} </span>
        </el-link>
        <div class="ele-upload-list__item-content-action">
          <el-link :underline="false" @click="handleDelete(index)" type="danger">删除</el-link>
        </div>
      </li>
    </transition-group>
  </div>
</template>

<script>
import { getToken } from "@/utils/auth";
export default {
  name: "FileUpload",
  props: {
    // 值
    value: [String, Object, Array],
    // 数量限制
    limit: {
      type: Number,
      default: 5,
    },
    // 大小限制(MB)
    fileSize: {
      type: Number,
      default: 5,
    },
    // 文件类型, 例如['png', 'jpg', 'jpeg']
    fileType: {
      type: Array,
      default: () => ["doc", "xls", "ppt", "txt", "pdf"],
    },
    // 是否显示提示
    isShowTip: {
      type: Boolean,
      default: true
    },
    // 数据类型 1 String 2Array
    dataType: {
      type: Number,
      default: 1,
    },
  },
  data() {
    return {
      // baseUrl: process.env.VUE_APP_BASE_API,
      // uploadFileUrl: process.env.VUE_APP_BASE_API + "/common/upload", // 上传的图片服务器地址
      baseUrl: "https://weishun-image.oss-cn-shenzhen.aliyuncs.com",
      uploadFileUrl: process.env.VUE_APP_BASE_API + "/file/uploadnewfile", // 上传的图片服务器地址
      headers: {
        Authorization: "Bearer " + getToken(),
      },
      timer: null,
      fileList: [],
      percentage: 0,
      isUpLoading: false,
    };
  },
  watch: {
    value: {
      handler(val) {
        if (val) {
          let temp = 1;
          // 首先将值转为数组
          const list = Array.isArray(val) ? val : this.value.split(',');
          // 然后将数组转为对象数组
          this.fileList = list.map(item => {
            if (typeof item === "string") {
              item = { name: item, url: item };
            }
            item.uid = item.uid || new Date().getTime() + temp++;
            return item;
          });
        } else {
          this.fileList = [];
          return [];
        }
      },
      deep: true,
      immediate: true
    }
  },
  computed: {
    // 是否显示提示
    showTip() {
      return this.isShowTip && (this.fileType || this.fileSize);
    },
  },
  methods: {
    // 上传前校检格式和大小
    handleBeforeUpload(file) {
      // 校检文件类型
      if (this.fileType) {
        let fileExtension = "";
        if (file.name.lastIndexOf(".") > -1) {
          fileExtension = file.name.slice(file.name.lastIndexOf(".") + 1);
        }
        const isTypeOk = this.fileType.some((type) => {
          if (file.type.indexOf(type) > -1) return true;
          if (fileExtension && fileExtension.indexOf(type) > -1) return true;
          return false;
        });
        if (!isTypeOk) {
          this.$message.error(`文件格式不正确, 请上传${this.fileType.join("/")}格式文件!`);
          return false;
        }
      }
      // 校检文件大小
      if (this.fileSize) {
        const isLt = file.size / 1024 / 1024 < this.fileSize;
        if (!isLt) {
          this.$message.error(`上传文件大小不能超过 ${this.fileSize} MB!`);
          return false;
        }
      }
      return true;
    },
    // 文件个数超出
    handleExceed() {
      this.$message.error(`上传文件数量不能超过 ${this.limit} 个!`);
    },
    // 上传失败
    handleUploadError(err) {
      this.$message.error("上传失败, 请重试");
      this.submitParent(0, false);
    },
    // 上传成功回调
    handleUploadSuccess(res, file) {
      this.fileList.push({ name: res.fileName, url: res.url });
      this.submitParent(100, true);
    },
    // 删除文件
    handleDelete(index) {
      this.fileList.splice(index, 1);
      this.submitParent(0, false);
    },
    // 获取文件名称
    getFileName(name) {
      if (name.lastIndexOf("/") > -1) {
        return name.slice(name.lastIndexOf("/") + 1).toLowerCase();
      } else {
        return name;
      }
    },
    // 对象转成指定字符串分隔
    listToString(list, separator) {
      let strs = "";
      separator = separator || ",";
      for (let i in list) {
        strs += list[i].url + separator;
      }
      return strs != '' ? strs.substr(0, strs.length - 1) : '';
    },
    returnData() {
      if (this.dataType === 1) {
        const url = this.fileList?.[0]?.url;
        // 将http替换成https
        if (url) {
          this.$emit("input", url.replace("http://", "https://"));
        } else {
          this.$emit("input", "");
        }
      } else {
        const urlArr = this.fileList.map((val) => val.url?.replace("http://", "https://"));
        this.$emit("input", urlArr);
      }
    },
    // 传递父组件数据
    submitParent(percentage, status) {
      this.isUpLoading = false;
      this.percentage = percentage;
      this.$emit("upload-progress", percentage);
      // this.$emit("input", this.listToString(this.fileList));
      this.returnData();
      clearInterval(this.timer);
    },
    // 上传进度
    handleUploadProgress(event, file, fileList) {
      if (!file) return;
      // 处理上传进度的回调
      const size = file.size / 1024 / 1024;
      if (size <= 1) {
        return;
      }
      if (!this.isUpLoading) {
        this.isUpLoading = true;
        this.timer = setInterval(function () {
          if (this.percentage < 99) {
            this.percentage += 1000 / size / 100;
            if (this.percentage >= 99) this.percentage = 99;
            const percentage = this.percentage
            this.$emit("upload-progress", percentage);
          } else {
            clearInterval(this.timer);
          }
        }.bind(this), 500);
      }
    }
  },
  destroyed() {
    clearInterval(this.timer);
  }
};
</script>

<style scoped lang="scss">
.upload-file-uploader {
  margin-bottom: 5px;
}

.upload-file-list .el-upload-list__item {
  border: 1px solid #e4e7ed;
  line-height: 2;
  margin-bottom: 10px;
  position: relative;
}

.upload-file-list .ele-upload-list__item-content {
  width: 60%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: inherit;
}

.ele-upload-list__item-content-action .el-link {
  margin-right: 10px;
}
</style>
